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teorth/PFR
Source indexedtheorem · leanprover/lean4:v4.33.0-rc1

entropic_PFR_conjecture_improv'

PFR.ImprovedPFR · PFR/ImprovedPFR.lean:828 to 845

Source documentation

entropic_PFR_conjecture_improv': For two GG-valued random variables X10,X20X^0_1, X^0_2, there is some subgroup HGH \leq G such that d[X10;UH]+d[X20;UH]10d[X10;X20]d[X^0_1;U_H] + d[X^0_2;U_H] \le 10 d[X^0_1;X^0_2]., and d[X^0_1; U_H] and d[X^0_2; U_H] are at most 5/2 * d[X^0_1;X^0_2]

Exact Lean statement

theorem entropic_PFR_conjecture_improv' (hpη : p.η = 1 / 8) :
    ∃ H : AddSubgroup G, ∃ Ω : Type uG, ∃ mΩ : MeasureSpace Ω, ∃ U : Ω → G,
    IsProbabilityMeasure (ℙ : Measure Ω) ∧ Measurable U ∧
    IsUniform H U ∧ d[p.X₀₁ # U] + d[p.X₀₂ # U] ≤ 10 * d[p.X₀₁ # p.X₀₂] ∧ d[p.X₀₁ # U]
      ≤ 11/2 * d[p.X₀₁ # p.X₀₂] ∧ d[p.X₀₂ # U] ≤ 11/2 * d[p.X₀₁ # p.X₀₂]

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
theorem entropic_PFR_conjecture_improv' (hpη : p.η = 1 / 8) :     H : AddSubgroup G,  Ω : Type uG,  mΩ : MeasureSpace Ω,  U : Ω  G,    IsProbabilityMeasure (ℙ : Measure Ω)  Measurable U     IsUniform H U  d[p.X₀₁ # U] + d[p.X₀₂ # U]  10 * d[p.X₀₁ # p.X₀₂]  d[p.X₀₁ # U]       11/2 * d[p.X₀₁ # p.X₀₂]  d[p.X₀₂ # U]  11/2 * d[p.X₀₁ # p.X₀₂] := by  obtain Ω', mΩ', X₁, X₂, hX₁, hX₂, hP, htau_min, hdist := tau_minimizer_exists_rdist_eq_zero p  obtain H, U, hU, hH_unif, hdistX₁, hdistX₂ := exists_isUniform_of_rdist_eq_zero hX₁ hX₂ hdist  have : d[p.X₀₁ # p.X₀₂] = d[p.X₀₂ # p.X₀₁] := rdist_symm  have goal₁ : d[p.X₀₁ # U] + d[p.X₀₂ # U]  10 * d[p.X₀₁ # p.X₀₂] := by    have h : τ[X₁ # X₂ | p]  τ[p.X₀₂ # p.X₀₁ | p] := is_tau_min p htau_min p.hmeas2 p.hmeas1    rw [tau, tau, hpη] at h    norm_num at h    have : d[p.X₀₁ # U]  d[p.X₀₁ # X₁] + d[X₁ # U] := rdist_triangle p.hmeas1 hX₁ hU    have : d[p.X₀₂ # U]  d[p.X₀₂ # X₂] + d[X₂ # U] := rdist_triangle p.hmeas2 hX₂ hU    linarith  have : d[p.X₀₁ # U]  d[p.X₀₁ # p.X₀₂] + d[p.X₀₂ # U] := rdist_triangle p.hmeas1 p.hmeas2 hU  have : d[p.X₀₂ # U]  d[p.X₀₂ # p.X₀₁] + d[p.X₀₁ # U] := rdist_triangle p.hmeas2 p.hmeas1 hU  refine H, Ω', inferInstance, U, inferInstance, hU, hH_unif, goal₁, by linarith, by linarith